Metal-clad gas insulated electrical switching equipment have a grounded metallic enclosure which contains an insulating gas such as sulfur-hexafluoride (SF.sub.6) gas at a relatively low pressure to isolate the electrical conducting components from the enclosure. Storage tanks for storing the insulating gas at a relatively high pressure are also contained within the enclosure. This gas upon a lowering of the ambient temperature will convert to its liquid phase causing a loss of its effective interruption value. The reclaiming of the liquified insulating gas and the replenishing of the insulating gas in the high pressure storage tanks has been a problem which the present invention solves.